This invention relates to a refrigerant gas compressor having a swash plate adapted for use in an automotive cooling system, particularly to an improvement in construction of gas passages formed within the compressor body.
Conventionally, a swash plate type compressor has a cylinder block which is axially dividable into two portions between which there is formed a swash plate chamber in which a swash plate rotates. Each of the two cylinder block portions is provided with at most three bores at equal distances along the circumference thereof. A low pressure gas passage is made in an interzone between two adjacent bores and a high pressure gas passage is made in another interzone between another two adjacent bores. A plurality of clamping bolts for uniting all principal members of the compressor in its axial direction extends through flange portions or projections radially outwardly extending from the both ends of the substantially cylindrical compressor body. Because of the presence of such projections, the general diameter of the compressor becomes greater, accordingly it is inconvenient to arrange the compressor within a narrow engine room of a motor vehicle.
In recent years, it has been tried to make the general diameter of the compressor body smaller to some extent by passing the clamping bolts through interspaces between two adjacent bores and by omitting the above-mentioned projections. However, due to the ever-increasing requirement for the high performance of motor vehicles, the space for installing various accessories including the refrigerant compressor is more restricted. Accordingly, it is required to make the compressor much smaller and to further improve its capacity. But, if the compressor body is made smaller in such a way as mentioned hereinbefore, it will be difficult to insure enough space for providing the refrigerant passages as well as the through holes for clamping bolts. In addition, if the number of bores is increased for the purpose of improving the capacity of the compressor, the space between two adjacent bores becomes much narrower. Consequently, it will be more difficult to arrange the refrigerant passages and the through holes for the clamping bolts. Owing to these structural problems, the above-mentioned requirements have not been fulfilled as yet.